Method of producing circulation in electrolytic processes.



H. -KOLLER dz P. ASKENASY.

METHOD OF PRODUCING CIRCULATION IN ELECTROLYTIC PROCESSES. APPLICATION FILED 00129.19

z zadde fizz 65250725 PATENTED JAN. 2, 1906.

UNITED STATES PATENT OFFICE.

HUGO KOLLER, OF VIENNA, AUSTRIA-HUNGARY, AND PAUL ASKENASY, OF NUREMBERG, GERMANY.

Specification of Letters Patent.

Patented J an. 2, 1906.

Application filed October 29, 1903. Serial No. 179,106.

To all whom it may concern:

Be it known that we, HUGO KOLLER, a subject of the Emperor of Austria-Hungary, residing at Vienna, in the Empire of Austria- Hungary, and PAUL AsKENAsY, a subject of the German Emperor, residing at Nuremberg, in the Empire of Germany, have invented certajn new and useful Improvements in Methods for Producing a Suitable Circulation of the Liquid in Electrolytic Processes, of which the following is a specification.

In all electrolytic processes which are carried out with the aid of a diaphragm there takes lace a mixing up of the products of the e ectrolysis through the diaphragm, whereby the yield is diminished in consequence of secondary reactions. For this reason but a weak concentration of the products obtained by electrolysis can be attained in the majority of cases. It has been proposed to obviate this mixing up of the products by the use of two diaphragms instead of one and by flushing the intermediate space between these two diaphragms by a continually-renewed rinsing solution. This method is attended with the drawback that a considerable quantity of the products formed at the anodes and at the cathodes, and particularly of the materials submitted to electrolytic decomposition, is lost by diffusion in the rinsing solution and cannot be recovered without the employment of some special measures.

The method forming the subject-matter of the present invention has for its object to restrict to the least possible extent the detrimental secondary reactions without any risk of wastage of the electrolyte in all those electrolytic processes in which the products formed at the anodes are of a gaseous nature and are insoluble in the liquid. This is attained by systematically lixiviating the diaphragms.

If in an electrolytical cellfor instance, during the electrolysis of sodium chlorid the electrolyte is caused to flow in zigzag through the interstices or spaces left open between the parts of the diaphragm starting from the anode compartment or from the part of the diaphragm next to it in such a manner that the greatest part of the way taken by the electrolyte is at right angles, or nearly at right angles, to the lines of theelectrical force and to the direction of the diflusion, this arrangement of the flow of the liquid within the diaphragm will produce the same result as any systematic lixiviation. The electrolyte introduced continuously or periodically at suitable intervals into the anode-compartment or into the part of the diaphragm next to the anode will at first meet those parts of the diaphragm which are farthest from the cathode-compartment and which are accordingly least impregnated with cathode-lye. The fresh electrolyte absorbs the detrimental cathode-lyes, carries them along with it on its way to the cathode, and thus removes them from the anode-compartment. This results in a systematic lix iviation ofthe diaphragm, since the greatest part of the material, which in consequence of difiusion is moving toward the anode, is being carried back again to the cathode by the flowing electrolyte. By such a flow of the liquid not only an increased yield is attained, but likewise a higher enrichment of the cathode-lye with the products of the electrolysis.

In order that the invention may be clearly understood, I have illustrated in the accompanying drawings different forms of apparatus by means of which the process may be carried out.

Figure 1 is a transverse sectional view of a form of apparatus employing superposed wedge-shaped diaphragms. Fig. 2 is a similar view of a modified arrangement in which the diaphragm is composed of superposed bricks or blocks arranged to break joint with one another; and Fig. 3 is a cross-section through Fig. 1, illustrating the slots or channels for facilitating the flow of the liquid.

The apparatus in Fig. 1 comprises a vessel 0, inwhich are arranged a series of superposed wedge-shaped diaphragms a, providing between them interstices b. e indicates a pipe for supplying the electrolyte to the vessel 0, which pipe is provided in its sides with openings d to permit the flow of the electrolyte freely into the presence of the anode p, the lower end of the pipe extending through one of the diaphragms to the space 1) between it and the adjacent diaphragm. n indicates the cathode located in a space or cathodechamber provided below the diaphragm, and f is an outlet-pipe leading from the cathodechamber. According to this construction the electrolyte in flowing through the interstices b describes a zigzag path between the wedgeshaped diaphragms and, together with the products of reaction, is withdrawn from the 5 cathode-chamber through the pipe f.

In Fig. 2 the general arrangement is the same, with the exception that in place of the wedge-shaped diaphragms a bricks a are employed, arran ed to form,- as it were, a wall,

and in operation the electrolyte is forced to flow through the interstices of the brick-wall diaphragm and around the bricks 0/ and extracts from the same the cathode products which have penetrated into the diaphragm segments by diffusion. In order to facili- '--tate the flow of theliquid, the interstices may, if so desired, be enlarged by suitable slots or channels, as indicated at g in Fig. 3.

In order to indicate the advantages to be derived from the use of such an apparatus over the known manner of operation, the following example is given: An apparatus was first tested for the electrolysis of sodium chlorid, which apparatus was provided with a diaphragm in the usual manner and in which there was a continual inflow and out-' flow of the anode-lye and cathode-lye. The same yielded with an average bath temperature of 60 and a potential of 4.5 volts a cathode-lye of ninety grams (N aOI-I) to the liter with a current yield of ninety-two per cent. Then an apparatus of the same size constructed according to my invention was sunk to sixty-five per cent.

We claim 5 1. In the art of electrolysis by the diaphragm process, the method which consists in causing a flow of an electrolyte toward and into the cathode-chamber in a direction substantially at right angles to the line of diffusion.

2. In the art of electrolysis by the diaphragm process, the method which consists in causing a flow of an electrolyte from the anode-chamber into thecathode-chamber in a direction substantially at right angles to the line of diffusion.

In testimony whereof we have hereunto set our hands 1n presence of two subscrlbing witnesses.

HUGO KOLLER. PAUL ASKENASY.

Witnesses:

JosEF RUBAsoH, ALvEsTo S. HoGUE. 

